The invention relates to a rapid coupling system.
Rapid coupling systems of the generic type are known. They serve for the connection of pressurised, medium-conducting lines and are used in the context of liquids, e.g. hydraulic oils, gasses and other appropriate media. Such rapid coupling systems comprise usually two coupling elements, wherein a first coupling element is a plug element and a second coupling element is a socket element. For coupling the plug element can be plugged into the socket element. The generic rapid coupling system serves also to connect lines which are under high media pressure. To this end the connection must be established either under pressure in the socket element and another time under pressure in the plug element of the coupling system. The connection can also be established under pressure in both coupling elements or in pressureless state of both coupling elements.
In rapid coupling systems designed for high media pressure, e.g. of 20 to 50 MPa in one of the two or in both coupling elements, pressure release valves are known for easier handling when establishing the coupling. With the help of such pressure relief valves it is possible to reduce the pressure in the coupling element by diverting a small amount of the medium to the face of the coupling element. This facilitates the connection of the two coupling elements of the rapid coupling system. The arrangement of pressure relief valves in both coupling elements is also known.
From DE 41 01 001 a coupling apparatus is known wherein a pressure relief valve is arranged in the interior of at least one coupling element which is actuated when connecting the plug element with the socket element. The pressure relief valve comprises a diverting channel for the media pressure and a cut-off element that is arranged in the pressure relief valve and can be actuated by an actuator. Upon actuation of the pressure relief valve the chambers of the coupling elements associated with it form communicating vessels which leads to a pressure compensation and allows to establish the coupling with less expenditure of energy.
A problem that occurs frequently with rapid coupling systems is that the pressure relief valves included in the coupling elements have a complicated structure. In addition to this contamination of the media result in dogged pressure relief valves and stiff rapid coupling systems. Another disadvantage is that depending on the type of rapid coupling system the plug element or the socket element or both coupling elements must be provided with the complicated pressure relief valves.
So the object of the present invention is to provide a rapid coupling system of the generic type which allows a simple way of easy coupling under avoidance of the above mentioned disadvantages in all pressure ranges.